Having looked at the QAcoustics website and seen what a 3050 speaker is I think as "to to man" said earlier it will be quite difficult to make a better speaker for 400 quid.
If I were you I would "play about a bit" with the 3050s, for example change the port tuning to a lower frequency by making the port a couple of centimeters longer . Better? Stuff something in the ports (reduced output below ca. 100Hz) do you like it?
Cut up a few squares of wood and clamp them with G-clamps onto the side of the cabinet to make the cabinet stiffer, better?
Get a bit of self adhesive damping material, similar to that used on car door panels,and glue it to the inside sides of cabinet (not too hard, you may want to remove it later), improved? Get some washed lambswool, lots in the outer Hebridies?, and put more absorbtion inside the cabinet, better? Bodge yourself a Helmholz resonator, like the 3050i to reduced the standing waves from the top/bottom of the cabinet (PM me if it is above your knowledge level)
Look at the crossover, if will probably have 2 capacitors and an inductor to filter the tweeter and one inductor and a capacitor to filter the bass units. Read the humblehifi capacitor test and buy yourself a few small value film capacitors to parallel up with what is already fitted. If it is an improvement you could buy some "boutique" capacitors and try those out.
Lots of things to try out, it won't cost a lot of money and you would learn a lot about speakers if you choose to build yourself a pair later.
Don't forget room acoustics, look at amroc or rew, try to understand the main modes of the your listening room with a sine signal sweep from 30 to 200Hz. If you have "boom" at certain frquencies see if it ties in the amroc or rew results and make yourself a few absorbers from roof insulation and listen to the effects.
Finally it have a hard tiled floor, buy yourself a nice thick sheepskin rug to add a bit of absorbtion in front of the speakers.
If I were you I would "play about a bit" with the 3050s, for example change the port tuning to a lower frequency by making the port a couple of centimeters longer . Better? Stuff something in the ports (reduced output below ca. 100Hz) do you like it?
Cut up a few squares of wood and clamp them with G-clamps onto the side of the cabinet to make the cabinet stiffer, better?
Get a bit of self adhesive damping material, similar to that used on car door panels,and glue it to the inside sides of cabinet (not too hard, you may want to remove it later), improved? Get some washed lambswool, lots in the outer Hebridies?, and put more absorbtion inside the cabinet, better? Bodge yourself a Helmholz resonator, like the 3050i to reduced the standing waves from the top/bottom of the cabinet (PM me if it is above your knowledge level)
Look at the crossover, if will probably have 2 capacitors and an inductor to filter the tweeter and one inductor and a capacitor to filter the bass units. Read the humblehifi capacitor test and buy yourself a few small value film capacitors to parallel up with what is already fitted. If it is an improvement you could buy some "boutique" capacitors and try those out.
Lots of things to try out, it won't cost a lot of money and you would learn a lot about speakers if you choose to build yourself a pair later.
Don't forget room acoustics, look at amroc or rew, try to understand the main modes of the your listening room with a sine signal sweep from 30 to 200Hz. If you have "boom" at certain frquencies see if it ties in the amroc or rew results and make yourself a few absorbers from roof insulation and listen to the effects.
Finally it have a hard tiled floor, buy yourself a nice thick sheepskin rug to add a bit of absorbtion in front of the speakers.
